A common law trust consisting of



June 19. 1924. 1,497,481

F. A. BULLINGTON INTERNAL COMBUSTION ENGINE Original Filed Aug. 19, 19205 sheets sheet] I ulW June 10, 1924. 1,497,481

F. A. BULLlNGTON INTERNAL COMBUSTION ENGINE Original Filed Aug. 19, 19205 Sheets sheet 5 June 10, 1924.

F. A. BULLINGTON INTERNAL COMBUSTION ENGINE Original Filed Aug. 19 19205 Sheets-Shest 4 June 10. 1924. v 1,497,481

F. A. BULLINGTON INTERNAL COMBUSTION ENGINE Original Filed Aug. 10, 19205 Sheets-Sheet 5 420 tion element Patented June 10, 1924.

UNITED STATES PATENT OFFICE.

FRAHL A. BULLINGTON. OF KANSAS CITY, MISSOURI, ASSIGNOB TO BURLINGTONMOTORS, OF KANSAS CITY. MISSOURI. A COMMON LAW TRUST CONSISTING' OFSOLOMON STODDARD, ERNEST E. HOWARD, AND FRANK A. BUIJIJINGTON.

INTERNAL-COMBUSTION FTTGINE.

Continuation of application Serial No. 404.592, filed August 18, 1920.Thlsappllcation filed June 10,

1922. Serial No. 567,286.

To all whom it may concord:

Be itknown that I. FRANK A. BULLING- TON a citizen of the United States,residing at Kansas City, in the county of Jackson and State of Missouri,have invented certain new and useful Improvements in Internal-CombustionEngines; and I do declare the following to he a full, clear, and exactdescri tion of the invention, such as will enab e others skilled in theart to which it appertains to make and use the same, reference being hadto the accompanying drawings, and to the figures of reference markedthereon which form a part of this specification.

This invention as herein illustrated and described relates to primemovers for genersting power and particularly to a motor in which anexpansihle motive fluid is employed to impart motion to pistons whichrotatc about a common axis.

This application is a continuation of an application filed by me on orabout August 19, 1920, Serial No. 404,592.

The particular type of motor involved includes co-operating pistonsprogressively rotatable about the axis of the power shaft. one pistonhaving relatively accelerated movement with respect to the other and thelatter having relatively retarded movement.

The pistons, however, rotate within the stator so that first one andthen the other hecomes the accelerated piston.

In actual practice I prefer to' arrange the istons in tirs, the pistonsof each pair ing rigid connected and they are diametrical y oppositelylocated on their respective shafts so that a movement of a iston in onepair will induce a correspon mg movement of the other iston in thatpair.

40 I also provide means w ereby first one set of pistons and then theother set becomes the accelerated pistons, and vice versa in altern'aterelation throughout the repeated cycles of themotor. Therefore, it willbe seen that the various sets of pistons become action elements andreaction elements in'alter'uate relation to generate power within themotor and communicate it to a transmission shaft. That is, if a iston ofone pair is the acor one explosion it is a, primary action element andthe other p ston of the same pair is a secondary action element to causesimultaneous compression action and intake action for succeedingcharges, and then one of the pistons of the other pair is a primaryreaction element and its mate in the same pair is a. secondary reactionelement to assist in a simultaneous scavenging or exhausting action of apreviously exploded char 0 and an intake ax:- ti on for a succeeding car e. After one piston has left the spark p ug as a primary actionelement, the next time it leaves the spark plug it will be a primaryreaction element.

Devices of the some generic principle as described above have beenprovided heretofore hut in order to maintain an operative co-actingrelation between the pistons of the various sets, it is necessar toprovide a movement controlling mec anism between the motor shaft and thetransmission shaft and in so far as I am aware. such movementcontrolling mechanism heretofore has been associated with a pivotalpoint or shaft eccentric to the piston shaft, with the result that thepower had to be taken from the motor by' some inefficient means.

It is of prime importance to the successful operation of a four cyclerotary combustion motor that each piston accelerate and retard at thesame rate so that there will be a uniform application of the owergenerated within the motor to the riven shaft or power shaft'of themotor for in the event that there are variations in the accelerating andretarding movements, obviously there will be a variable in the angularspeed of the driven shaft which might be termed a jumpy action.Therefore, it is an important feature of my invention that the links ebetween the pistons and the power sha t be so constructed and soco-ordinate that under all conditions there will be a uniformalternating accelerating and retarding rotative movement of the pistons.

Prior to m invention istons have been connected on controlled y linksbut in all devices of which I have know edge the linka' was soconstructed that variables woul occur in the accelerating andretardingmovcments of the pistons. Some attempts have been made toovercome this recognized disadvantage but such structures 10! haveincluded cams or gears for controlling the movements of the pistons.Where gears are used. obviously, the mechanism was mechanicallyimpracticable because the teeth could not withstand the shocks or blowscommunicated to them at the moment of explosion or ignition of the fuelcharge. Likewise where cams were employed. they were associated withrollers which passed over them and these also caused hammer blows orlocal shocks to the rollers and to definite parts of the cam at eachexplosion so that in actual practice they could not. stand up.

My invention contemplates means for conmeeting the pistons to the drivenshaft of the motor by suitable linkage or mechanism which will controlthe movementot the pistons about a common axis so that they will haverelative movement to compress fuel charges to combustible pressures andwhereby the pistons will have alternate uniform accelerating andretarding rotative move- ..ments to insure uniform application of theexpansive forces of the ignited charges applied-to complementarv pistonsto thereby. through the linkage, rcitatc the driven shaft with uniformapplication of power as well as to insure balanced I'otative movement ofthe istons.

T is I accomplish by so constructing the linkage for connecting thepistons to the driven shaft that all of the parts will have constantmovement during the operating periods of the motor so that there will beno stationary parts to receive the impacts of the exploded charges. Theconstantly rotating connecting linkage between the pistons and thedriven shaft will absorb the impact of the exploded charges during theirmovement and during the time that. there will be relative movementbetween the operating parts of the linkage so that. a hammer blow ordirect impacting contact will not result as would be. the. ease Where astationary cam, for example, was the guiding clement. about which pinsor shafts of the link members moved or where a fixed gear received allof the force of the exploded charges from a pinion tooth.

1th uniform applications of power from the successive explosions,uniform angular rotation of the driven shaft may be. provided andinsured by a fly wheel thereon.

In the construction illustrated in this application. l utilize gears butthese gears do not receive the full impact from the exploded charges:they receive a resultant force of the exploded charges. Such impact isabsorbcd in the linkage, the gears being utilized merely as deliveringthe resultant work ing force or torque to the driven shaft and areimportant parts in controlling the rotativc movement of the pistons andthe re sultant working force to the driven shaft.

It is to be noted, however, that the objeetions heretofore referred towith respect to the inclusion of gears in a connecting linkage betweenthe pistons and the driven shaft is not present in. my invention onaccount of the fact that the shocks are absorbed at a. point in thelinkage between the pistons and the gears which have been heretoforereferred to. i

Attention is called to the fact that the entire linkage planetates aboutthe axis of the pistons and about the axis of the driven shaft and thatthis planetary movement continues throughout the entire operating cyclesof the motor.

In the drawings,

Fig. l is a perspective view of the invention part1 in section to showthe interior of the engine casing and the interior of the crank case and(o-operating mechanism.

Fig. 2 is a vertical. longitudinal, sectional View, olle ol' the pistonsbeing shown in section. to illustrate the arrangement of the packing. 1/

Fig. I, is a vjiaw of the motor with the outer half of the casingremoved on the line 33 of Fig. 2, looking in the direction of the arrow.

Fig. 4 is a cross sectional view on the line 4-4 of Fig. 2. i

Fig. 5 is a sectional view on the line 55 of Fig. 3. A

Fig. 6 is a diagrammatic view showing the positions of the pistons andthe piston controlling linkage when the crank is at upper dead center.

Fig. 7 is a diagram showing the position of the pistons when the crankis advanced 22% degrees from the position shown in Fig. 6.

Fig. 8 is a diagrammatic view showing the position of the pistons andthe piston controlling linkage when the crank has advanced -15 degreesfrom the position shown in Fig. 6.

Fig. 9 is a diagrammatic view showing the position of the pistons andthe linkage when the crank has advanced G7,} degrees from the positionshown in Fig. 6. V

Fig. 10 is a diagrammatic view showing the positions of the pistons whenthe crank has traveled one-fourth of a revolution to a side dead centerposition or one complete ltlt) power stroke, it being understood thatthe engine shown provides four crank dead center positions and fourexplosions to a complete revolution ofthe motor shaft and that theengine is designed to operate on the principle of a four-yelehydrocarbon engme.

The stator is shown as consisting of a cue ing comprising the halves 10and 10', the outer one 0 of which is removable to permit access to thestator. The interior of the stator is elliptical in cross section butformed to provide a circumferential chambe! for the'pistons. The casingis proi'idcd with a water jacket 11, having an inlet 12. and an outlet13 whereb' a cooling fluid may be circulated about he stator torlissipate heat generated by the explosions with in the motor casing.The two halves may communicate through the aligning ports 11 so that theWater may circulate through the water jacket.-

The stator is provided at an appropriate oint with a spark plug 14,having a chamr 15 about the spark plug point communicatin with theinterior of thestator whereby t e charge admitted to the stator may beex loded when under compression. As shown t e spark plug is at the topof the stator while the irlet is near the bottom thereof, thearrangement of inlet being best shown in Figs. 3 and 5.

The inlet may consist of a chest or valve casing 16 having a pluralityof ports 17, 18, 17 and 18, the latter progressing from the controlvalve 19 into the stator chamber. The valve 19 is provided with op)ositely located ports 20 and 21 whereby w en the valve is turned, theeffective port and oassage area between the carburetor and the interiorof the stator casing can be regulatd; that is, maintained at asufficient effective area to insure the most efiicient vacuum conditionbetween the engine and the carburetor. In other words, the arrangementof intake is such as to insure the proper manifold or port area for thespeed and temperature of the motor.

The motor is provided with an exhaust port 22 near the lower side of thecasing and with an auxiliary exhaust port .23 and a preliminary intakeport 24 between the main intake and the main exhaust, as clear- 1yindicated in Fig. 3.

. Within the stator is a plurality of pistons arranged in pairs, theistons of one pair being designated 25 an 26 on the hub or web 27carried by the piston shaft '28. The pistons of the other pair aredesignated 29 and 30 carried by the hub or web 31, mounted on the hollowpiston shaft or sleeve 32 sleeved upon the shaft 28 and extendingthrough the bearing 33, illustrated a an integral part of the statorcasing. Therefore, the pistons 25 and 26 have synchronous movement, onewith the other but inde endent movement with respect to the pistons 29and 30. The pistons 29 and 30 have svnchronous movement one with theother but independent movement with respect to the pistons 25 and 26.

All of the pistons are providedwith arcuate piston rings or strips 34,which are normally pressed outwardly by coiled springs 35 in recesses inthe pistons, it being apparent by reference to Figs. 1 and 2 that theistons on the hub 27 are substantially semi-circular and extend over thehub 31',

and that the pistons 29 and 30 on the hub 31 overlie the hub 27, asclearly shown in Fig. l. The lower ed es of the pistons which overliethe complementary hubs are provided with springprcssed packing strips30. as will be clearly seen by reference to Fig. 2, and the outer facesof the hub are provided with coniplcnientary scalin rings 37 and 38which cooperate to provit e close clearances to prevent leakage of theexplosive charge.

The inner faces of the complementary hubs 27 and 31 are provided withsplit ring lpackin'gs 39 and 40, each bearing and rubing against theother but carried freely and independently by or within its particularpiston hub, this being an advantage over a solid or one-piece packingrin since the split packing ring more effectual y seals or packs thejoint between the two piston hubs even in the event of slightirregularities or warping between the two complementary piston hubs 27and 31.

As heretofore explained, it is desired to provide certain relativemovements between the two pairs of pistons during the cycle of operationso that first one pair of pistons of a set becomes the accelerated oraction pistons while the other pair is reaction pistons and then on thenext explosion, the pair of pistons which has previously been the aceeerated or action pistons becomes the retarded or reaction pistons andthe pistons which in the first instance were the retarded or reactionpistons then become the aeceler ated or action pistons, the relativefunctions of the two pairs of pistons alternating at each explosion. 1

The mechanism for accomplishing the proper functioning of the variouspistons includes a coupling for connecting t e pis ton shafts to thetransmission element which may be the crank shaft or gear shaft,according to the manner of transmitting the power. The transmissioncrank shaft 41 is shown as in line with and concentric with acounterbalance weight 45 and havin a crank 46 having a (rank in 48, on wich is rotatably mounted a pinion :ar 47, mesh ing-with the internalteeth 48 of a static! ary, internall toothed ring gear 49, con,- centricwitht 1e shafts 28' and 41 but eccentric o the axis of the pinion. Theinternally toothed ring gear 49 is rigidly sup ported by the casing 43within the ofiset portion 50, shown as fixed to the bearing 42 andeasing so that the pinion gear ,will roll over the teeth 48, rotateabout its axis or crank 46, and revolve bodily about the axis of thecrank shaft 41. Fixed to the pinion gear 47 and rotatable therewithabout the axis of the crank pin 46' is a bar 5i. tho oppositely disposedarms 52 and 53 of which constitute slotted cranks. the slots 5i and 55receiving sliding heads or hearing blocks 56 and 57, to which crank arms58 and 59 on the piston hollow shaft 32 and piston shaft 28 respectivelyare pivotally connected.

The crank arms 58 and 59 are provided with counterbalance weights 58"and 59' at their free ends, as shown, to assist in carrying over deadcenters and to facilitate smooth running of the rotating parts of themotor.

In order to provide an interconnecting. supporting structure or couplingbetween the crank 46 and the piston shaft 28. I have provided a link, orfloating bearing member 60, mounted on and carried by the crank 46. andhaving a bearing engagement with the shaft 28, at its crank end. thelink being rovided-with a counterbalance weight 61.

e counterbalance weight 61. together with the counterbalance weight 46on the head 44 of shaft 41, provides the necessary counterbalance forthe crank pin 46, the pinion %;47, and the bar 51.

e power shaft 41 is shown as being provided with a fly wheel pulley 62from which power may be transmitted. to what ever driven elements are torespond to the action of the motor. I prefer to extend the piston shaft28 through the outer half of the casing and provide lugs 63 and 64 t won so that a crank may be sleeved over 1 end of the shaft 28 in theusual way 101* cranking the engine.

When the parts are assembled as shown and the motor is turned oven-thepistons rotating in a clockwise direction, so that the initial charge isdrawn in. and trapped between the pistons 26 and 30,, or example, whenthey occupy the positions of 29 and 26, it is apparent that the piston26 will move faster on the intake stroke than the piston 30 so as todraw in the charge, the accelerated movement ceasing; by the time thepiston 30 has closed off the intake ort. Then. by reason of the linkage,the piston 30 will become the accelerated piston to compress the chargeuntil the pistons are substantially in the positions of the pistons 25and 29 in Figs. 3 and 6.

In this position of istons the crank 46 and connecting mechanism is in aneutral or dead center osition and a slight movement forward will carryover dead center, at which time ignition of the compressed charge offuel between the pistons will be caused by the spark log and on electrictimer (not shown). he resulting explo sion and expansion of the chargewill ac celeratc the piston 26, the piston 30 being slightly retardedduring this time but also moving forward until the accelerated piston 26reaches the limit ofits expansion stroke, in which position it uncoversor opens the exhaust port whereupon a second explosion occurs in thesucceeding chamber. The retarded piston 30 will then be accelerated toclose the gap or chamber between the two pistons between which theexplosion charge had just previously been ignited and thereby cause thescavenging of the burnt gas from the chamber.

\Vhen the pistons are in the position shown in Fig. 6. all parts arepractically on. dead center so the hearings or blocks 56 and 57 ar equaldistances on the bar 51 from the pivot or crank pin 46. but when thepisstons move slightly forward in a clockwise direction (Fig. 6), thebar 51 will be rotated about the crank pin 46 in a clockwise direction,and the distance between the crank pin and the block 57 y, will begreater than the distance between the crank-pin and the block 56.Therefore. the greater pull will he on the arm 53 to cause the rotationof the pistons to be in the direction of the arrow. causing the forwardpiston relative to an explosion to at all times be the accelerated oraction piston and the rear piston the retarded or reaction piston, andthe crank pin 46 and the bar 51 to revolve bodily about the axis of thecrank shaft 41 in a contraclockwise direction and thereby cause therotation of the crank shaft 41 in the same direction. Since first 25 and26 are the forward pistons and then 29 and 30 become the forwardpistons, it follows that alternately the two sets of action and reactionpistons during the cycle of o erations.

en the piston 26 has reached the limit of its explosion stroke, therewill have been a charge of fuel compressed between 25 and 30 and as themomentum carries the link connection. cranks. etc. over dead center,carrying 30 and 25 past dead center, there will be another explosionbetween 30 and 25 so that 30 becomes the accelerated piston and thespace between 26 and 30 will exhaust. When the piston 30 passes andcloses the exhaust port 22, its accelerated and scavenging action willnot have been completed and for the completion of this action, theremainder of the exploded or burned gas will he passed out through theauxiliary exhaust port 23. As soon as the piston 30 closes oil 23. 26will be uncovering the port 24 so as to draw in a preliminary charge offresh air before uncovering the inlet port from the fuel supply. Afterthe piston 26 passes the inlet port, the effective volume of the spacebetween 26 and 30 will be increased to take the full charge of fuel andthen begin to compress the charge because the piston 29 will beaccelerating under the influence of its exploded charge, the peakpistons become izo of the com ression being reached at dead center or ajacent to the spark plug so that the charge will he exploded at the hihest point in its compression. Thus it wil be seen that a four-cycleoperation of the en gine takes place after each explosion.

It will also be aparent that the effective port area for the in ct maybe controlled by the valve 19 so that the port. area can be ofappropriate size to insure the most oilicient vacuum condition betweenthe engine and the carburetor.

It will be further apparent that after each ex losion, the end of thecrank for the acce erated piston. that is. the advanced piston, will bea reater distance from the axis of rotation o the bar ri id on thepinion than will the outer end o the crank for the complementaryreaction piston. Therefore, the greater pull will be exerted on thatportion of the bar co-operatin with the advanced piston responding to te explosion, causing the bar to revolve about the axis of the istonshafts in the direction of rotation of t e piston shaft by reason of thefact that the pinion rolls with the bar on the teeth of the internalgear. The direction of rotation of the transmission element will bereversed with respect to the motor piston shafts, the movement beingsuch that the engine will continue to rotate in the direction in whichit is started.

In order to bring about proper performance of the workin parts of the"engine in that each piston will accelerate and retard at the same rateto provide a uniform application of the power generated within the motorto the driven shaft or power shaft, it is recommended that the en ine beconstructed in accordance with t e diagrammatic illustrations shown inFigs. 6 to 10, both inclusive.

In Fig. 6 the pistons are shown in their proper relations at thebeginning and ending of each stroke action. That is. the two pistons 29and 25 are in the position with the charge compressed between them. The

grees. an

pistons 26 and 30 have exhausted. The position of the bar 51 (rotatablewith the pinion gear 47 and about the axis of the crank pin 46' on whichthe pinion gear is mounted) is perpendicular to the crank radius, whichis the dead center of the mechanism and occurs four times during onerevolutionof the motor. The least angular distance between cooperatingpistons at any 'time is 53 degrees and the greatest possi Le distancebetween any two pistons is 127 degrees. The angular StIOiB action,therefor c, of complementary iistons is the sum of 127 de rees and 53degrees, or 180 detheir difference, or 74 degrees. In Fig. 6 thedistance between the radial centers of the pistons is 53 degrees, as in-B5 (heated by the angle cd. Rotation of the crank 47 in acontra-clockwise direction is accomplished by a rotation of the pistonsabout the motor axis in a clockwise direction and in Fig. 7 the crank 46has rotated 22'} degrees from the position shown in Fig. 6. The bar 51has rotated 45 degrees about the axis of the crank pin, the piston 25has advanced 27 degrees, and the piston 29 has advanced 18 degrees fromtheir respective positions, the positions of the pistons 29 and 25 beingindicated at angle 0 and d. The distance between them has been increased9 degrees and an iniaginar point midway be tween them, as indicatedl i22% degrees from the point 5 (Fig. 6). The piston 25 has received anaccelerated rotation of 41} degrees and the piston 29 has been netarded4% degrees-during the 22,5 degrees of rotation of the motor. In Fig. 8the parts are shown in position with the crank pith 46"advanoed 45degrees from its position in Fig. 6, and the bar 51 has been rotated 90degrees about the crank pin. The piston 25 has advanced 63 degrees andthe piston 29 has advance 261} e rees from their initial positions, asshown in ig. 6. The imaginary point midway between the two istons, asrepresented by b in Fi 6, has a vanced to the position indicated y b" inFig. 8 and the angular movement of the piston 25 in advance of theposition indicated in Fi 7 is indicated by the angle 0! There ore, thepiston 25 has received an accelerated rotation of 181} de' grees and thepiston 29 has been retarded in its movement of 18% degrees.

In Fig. 9 the crank nin 46' is shown as advanced 67 degrees from thepoint it as: sumed in Fig. 6. The bar 51 has been r0- tated 135 degreesabout the crank pin, the radial center of the piston 25 is indicated atcenter of the iston 29, as represented by the line 0", has een advanced35 de rees from the position shown in Fig. 6. T to angular distancebetween the pistons 29 and 25 has increased 65 degrees and the originalmidway point between the pistons, as indicated by b in Fig. 6, hasadvanced 67) degrees. Thus the nston 25 has received an acceleratedrotationof'32} degrees and the piston 29 has received a retardedrotation of 32% degrees. Therefore, the mean angle of rotation of bothpistons is 67% degrees, the same as that of the crank pin 46'.

In Fig. 10 the arts are shown with a stroke action comp ctcd. The crankpin 46' has advanced 90 degrees, the bar 51 has been rotated 180 degreesabout the crank pin and is again perpendicular to the crank radius, thepiston 25 has advanced 12j" degrees, and the piston 29 has adyanced 50degrees to the position previously occupied by the iston 25 in Fig. 6.The movements of the pistons, bar and crank pin just enumerated in conyb, has advanced nection with the diagrams have been those which takeplace between any two pistons from the time of the explosion throughthe" respectively so any movement which is imparted to either piston 29or 25 will impart a corresponding movement to a eomple mentary piston utat a different cycle position during the rotation of the motor. Forexample, when the piston 25 is moved out under the expansion of theexploded charge away frcm 29, its complementary piston 26 is moving intocharge-compressing position toward 29, and 30 is moving past the exhaustport and the space between 25 andBU is being exhausted of gas whichhaspreviously done useful work. i

In order to simplify the des'ciription it has deemed simply describe theactionwinstons during the four cycle action of the motor since themovements of any other set of pistons can be readily ascertamed inconnection therewith.

Attention is called to the fact that the diagrams and the ex lanationsthereof are simply illustrative 0 an engine in which the stroke of thepiston is 68 degrees, it being apparent that the relative movements ofthe various co-ordinating parts will pro portionately vary with engineshaving piston strokes of different lengths.

From the foregoing it will be seen that l have provided a motorpossessing the H1 herent, theoretical advantages of a rotary enginewithout the inclusion of the mechanical disadvantages. The motor is soarranged that advantage may be taken of the movement value of a fourcycle system of reciprocatory en ine without the inherent mec anicaldisa vantages thereof, such as the use of clack valves and the like. Itill also be seen that the arrangement of the parts is so designed that ahigh degree of efficiency is insured with the given consumption ofmotive fluid.

What I claim and desire Letters Patent is:

1. .In a rotary motor, a casing, pistons to secure by therein,concentric shafts for the pistons,

one of which is sleeved upon the other. a driven crank shaft spaced frombut ('(mcentric with the piston shafts, the crank on the crankshaftrotating about an axis com mon to the concentric piston shafts and thecrank shaft, and means connecting the crank and .iston shafts inco-operativc relation.

2 in a rotary motor. :1 casing, pistons therein, concentric shafts forthe pistons. one of which is sleeved upon the other. a driven cranlsskaft spaced from but concentric withtl ie pistwshafts. the crank on thecrank shaft rotating about an axis common to the concentric pistonshafts Ind the crank shaft, and means connecting the crank and pistonshafts in co-operative relation, said means including a rotatable barcarried by the crank, and cranks on the piston shafts having slid-ableengagement with said bar.

3. In arotary motor, a casing, pistons therein, concentric shafts forthe pistons, one of which is sleeved upon the other, a driven crankshaft spaced from but concentric with the piston shafts, the crank onthe crank shaft rntatingabont an axis common to the com-cmric pistonshafts and the crank shaft. and means connecting the crank and pistonshafts in co-operative relation, said means comprising a slotted barrotatable with the crank but movable in a direction opposite to therotation of the crank, and cranks on the piston shafts having slidableenga enient with said bar.

4. n a rotary motor, a casing, pistons therein, concentric shafts forthe pistons, one of which is sleeved upon the other, a driven 1 ch shaftspaced from but concentric wi the piston shafts, the crank on the crankshaft rotating about an axis common to the concentric piston shafts andthe crank shaft, and means connecting the crank and piston shafts inco-operative relation, said means includin a rotatable bar carried bythe crank, era 5 on thepiston shafts having slidable engagement withsaid bar, and a link between one of the iston shafts and a crank on thecrank sha 5. In a rotary motor, a casing, pistons therein, concentricshafts for the pistons, one of which is sleeved upon the other, a powertransmission element spaced from but concentric with the piston shafts,a crank on the power transmission element, means connecting the crankand the piston shafts in co-operative relation, said means including arotatable bar carried by the crank, cranks on the piston shafts havingslidable on agement with said bar, and a counterba ancing link betweenone of the piston shafts and a crank on the power transmission element.

6. In a rotary motor, a casing, pistons therein. concentric shafts forthe pistons, one of which is sleeved upon the other, a powertransmissionclement spaced from but concentric with the piston shafts, acrank on the power transmission element. a pinion gear rotatable on saidcrank. an internal gear about the pinion with which the teeth of thepinion mesh to provide a ro'llin contact, a bar rigid with the pinion,an cranks on the piston shafts in sliding engagement with said bar.

7. In a rotary motor, a casing. pistons therein. concentric shafts forthe pistons, one of which is sleeved upon the other, a powertransmission element s need from but concentric with the piston afts, acrank on the power transmission element, a pinion gear rotatable on saidcrank, an internal gear about the pinion with which the teeth of thepinion mesh to provide a rolling contact, a bar rigid with the pinion,cranks on the piston shafts in sliding engagement with said bar, and afloating bearing connecting one of the piston shafts and the crank.

8. In a rotary motor, a casing, pistons therein, concentric shafts forthe pistons, one of which is sleeved upon the other, a powertransmission element spaced from but concentric with the piston shafts,a crank on the power transmission element, a pinion gear rotatable onsaid crank, an internal gear about the pinion with which the teeth ofthe pinion mesh to provide a rolling contact, a bar rigid with thepinion, cranks on tin piston shafts in sliding engagement with said bar,and a floating bearing connecting one of the piston shafts and thecrank, said bearing comprising a counter-balancing link.

9. In a rotary motor,a casing, pistons therein, concentric shafts forthe pistons,

one of which is sleeved upon the other,

cranks carried by the shafts bearing blocks loosely engaged by the endsof the cranks, a power transmission element, a crank carried thereby,and a rotatable bar mounted on the crank and revolving in a directionopposite to the rotation of the power transmission element, said barhaving slots engaged by the blocks on the cranks of the piston shafts.

10. In a rotary motor, a casing, pistons therein, concentric shafts forthe pistons, one of which is sleeved upon the other, cranks carried bythe shafts, bearing blocks loosely engaged by the ends of the cranks, apower transmission element, a crank carried thereby, a rotatable ba'rmounted on the crank and revolvin" in a direction opposite to therotation of the power transmission element, said bar having slotsengaged by the blocks on the cranks of the piston shafts, and a linkconnection between one of the piston shafts and the crank.

11. In a rotary, motor, a casing, pistons therein, concentric shafts forthe pistons, one of which is sleeved upon the other, a powertransmission element spaced from but. concentric with the piston shafts,a crank on the power transniission element, means connecting the crankand the piston shaftsin cooperative relation, said means including arotatable bar carried by the crank,

cranks on the piston shafts having operative engagement with said bar,and an inter-coir necting means between one of the piston shafts and acrank on the power transmission element.

12. In a rotary motor, a casing. pistons therein, concentric shafts forthe pistons, one of which is sleeved upon the other. a powertransmission element spaced from but concentric with he piston shafts, acrank on the power transmission element, a pinion gear rotatable on saidcrank, an internal gear about the pinion with which the teeth of theinion mesh to rovide a rolling contact, a liar rigid with t 1e pinion,and means on the piston shafts in operative. cngagement with said bar.

3. In a rotary motor, a casing, pistons lllcrcin, concentric shafts forthe pistons, one of which is sleeved upon the other, a powertransmission clement spaced from but concentric with the piston shafts,a crank on the power transmission element, a pinion gear rotatable onsaid crank, an internal gear about the pinion with which the teeth ofthe pinion mesh to provide a rolling contact, a bar rigid with thepinion, cranks on the piston shafts in o erative engagement with saidbar, and a oating bearing connecting one of the piston shafts and thecrank.

14. In a rotary motor, a casing, pistons therein, concentric shafts forthe pistons, one 1, hich is sleeved upon the other, a power sansmissionelement 5 aced from but concentric with the piston siafts, a crank onthe power transmission element, means connecting the crank and thepiston shafts in cooperative relation, said means including a rotatablebar carried by the crank, cranks on the piston shafts l'iaving operativeengagement with said bar, and inter-connecting means between one of thepiston shafts and a crank on the power transmis sion element.

15. In a rotary four cycle combustion motor, a cylindrical casing, pairsof pistons therein, rotating about a common axis having relativemovement to compress fuel charges to combustible pressures, means forigniting the compressed charges, a driven shaft, and linkage connectingthe pistons to the driven shaft, one of the members of the linkagelnn'iug planetary movement about the axis of the driven shaft. thelinkage being effective to cause uniform alternate accelerating andretarding roiative movenwnts of complementary pistons of complementarypairs to insure balanced rotative movement of the pistons.

16. In a rotary four cycle combustion motor, a cylindrical casing-pairsof istons therein, rotating about a common axis having relative movementto compress file, charges to combustible pressures. means for ignitingthe comprcssc charges, a driven shaft. and linkage connecting thepistons to the driven shaft, one of the members of the linkage havingplanetary movement about the axis of the driven shaft, the linkage beingeffective to cause uniform alternate accelerating and retarding rotativemovement of complementary pistons of complementary pairs to insureuniform application of the ex ansive forces of the ignited chargesapplie to complementary pistons to thereby rotate the driven shaft atuniform angular speed. i

17. In a rotary four cycle combustion motor, a cylindrical casing, pairsof pistons therein, rotating about a common axis ha ving relativemovement to compress t'uel char es lo combustible pressures, means for initlng the compressed charges, a dri vi-n shaft, and linkage connectingthe pistons to the driven shaft, one of the members of the linkagehaving planetary movement about the axis of the driven shaft, thelinkage bem effective to cause uniform alternate accefiaratin andretarding rotaiive nlovenlenis of complementary pistons of complementarypairs to insure balanced rotative movement of the pistons and uniformapplication of the expansive force of the ignited eha'rgi-s applied tocomplenn-otary pistons to there-- by rotate the driven shall at unif-ormangle lar speed.

1.8. In a four cycle rotary combustion motor, a cylindrical casin,--pairs of pistons therein rotative about a common axis, the pistons ofone pair having relative move ment with respect to the pistons of theircomplementary pair to compress fuel charges to combustible pressures,means for i niting the compressed charges, a driven shaft, and planetarylinkage between the respective pairs of pistons and the driven shaftoperating to cause uniform acceleration and retardation of thecomplementary pistons of complementary pairs, each piston retarding atthe same rate of speed as it was previously accelerated to insureuniform application of the expansive force of the ignited charge appliedto the complementary pistons to thereby rotate the driven shaft atuniform angular speed.

19. In a four cycle rotary combustion motor, a cylindrical casing, pairsof pistons therein rotative about a common axis, the pistons of one pairhaving relative movement with respect to the pistons of theircomplementary pair to compress fuel charges to combustible pressures,means for igniting the compressed charges, a driven shaft, planetarylinkage between the re spective pairs of pistons and the. driven shaftam operat ng to cause uniform acceleration and retardation of the.complementary pistons of complementary pan-s.

each piston retarding at the same rate (it .sp eed as it was previouslyaccelerated to insure uniform application of the expair sive force ofthe ignited charge applied to the complementary pistons to therebyrotate the driven shaft at a unit rm angular speed. and a gearingassociated ith the linkage for rotatin the part of the linkage connectedto t e shaft about an 'orbit concentric with the axis about which thepistons rotate.

20. In a four cycle rotary combustion motor, a cylindrical casing, pairsof pistons therein rot alin; about a common axis, the pistonsot-complementary pairs having relative movement to compress fuel chargesto combustible pressures, means for igniting the compressed charges, adriven shaft concentric with the axis about which the pistons rotate andhaving a crank, a gear cecentrieally mounted with respect to the shaftand supported on the crank, a secohd gear with which the first gearmeshes, and planetary linkage having comiection with the crank and withthepistons to cause uniform alternative awftiration and retardation ofthe complementary pistons of complementary pairs to insure uniformapplication'oi' chm-expansive force of the ignited charge applied to thecomplementary pistons. each piston accelerating and retarding: at thesame rate, the linkage between the pistons and the crank being effectiveto absorb the explosive shocks so that the gears will be free of suchshocks to serve as directional gears for the crank on the driven shaftand through the linkage cause rotation of the pistons.

91. In a four cycle rotary combustion motor, a cylindrical casing, pairsof pistons therein rotating about a common axis, the pistons oicomplementary pairs having relative movement to compress fuel charges tocombustible pressures, means for igniting the compressed charges, adriven shaft concentric with the axis about which the pistons rotate andhaving a crank, a. gear eccentrirally mounted with respect to the shaftand supported on the crank, a second gear with which the first gearmeshes, and planetary linkage having sliding connection with the crankand with the pistons to cause uniform alternative acceleration andretardation of the complementary pistons ol' complementary pairs toinsure uniform application of the expansive force of the ignited chargeapplied to the complementary pistons, each piston accelerating! andretarding at the same rate, the linkagehetween the pistons and the crankbeing effective to absorb the explosive shocks so that the gears will befree of such shocks to serve as directional gears for the crank on thedriven shaft and through the linkage cause rotation of the piston.

in testimony whereof I aliix my signature.

FRANK A. BULLINGTON.

